Re: [RFC 1/4] hashtable: introduce a small and naive hashtable

From: Sasha Levin
Date: Thu Aug 02 2012 - 09:03:47 EST


On 08/02/2012 01:23 PM, Sasha Levin wrote:
>> #define DEFINE_HASH_TABLE(name, length) struct hash_table name = { .count = length, .buckets = { [0 ... (length - 1)] = HLIST_HEAD_INIT } }
> The limitation of this approach is that the struct hash_table variable must be 'static', which is a bit limiting - see for example the use of hashtable in 'struct user_namespace'.
>

What if we just use two possible decelerations? One of static structs and one for regular ones.

struct hash_table {
size_t bits;
struct hlist_head buckets[];
};

#define DEFINE_HASHTABLE(name, bits) \
union { \
struct hash_table name; \
struct { \
size_t bits; \
struct hlist_head buckets[1 << bits]; \
} __name; \
}

#define DEFINE_STATIC_HASHTABLE(name, bit) \
static struct hash_table name = { .bits = bit, \
.buckets = { [0 ... (bit - 1)] = HLIST_HEAD_INIT } }
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/